Retinal glycoprotein enrichment by concanavalin a enabled identification of novel membrane autoantigen synaptotagmin-1 in equine recurrent uveitis.

Complete knowledge of autoantigen spectra is crucial for understanding pathomechanisms of autoimmune diseases like equine recurrent uveitis (ERU), a spontaneous model for human autoimmune uveitis. While several ERU autoantigens were identified previously, no membrane protein was found so far. As there is a great overlap between glycoproteins and membrane proteins, the aim of this study was to test whether pre-enrichment of retinal glycoproteins by ConA affinity is an effective tool to detect autoantigen candidates among membrane proteins. In 1D Western blots, the glycoprotein preparation allowed detection of IgG reactions to low abundant proteins in sera of ERU patients. Synaptotagmin-1, a Ca2+-sensing protein in synaptic vesicles, was identified as autoantigen candidate from the pre-enriched glycoprotein fraction by mass spectrometry and was validated as a highly prevalent autoantigen by enzyme-linked immunosorbent assay. Analysis of Syt1 expression in retinas of ERU cases showed a downregulation in the majority of ERU affected retinas to 24%. Results pointed to a dysregulation of retinal neurotransmitter release in ERU. Identification of synaptotagmin-1, the first cell membrane associated autoantigen in this spontaneous autoimmune disease, demonstrated that examination of tissue fractions can lead to the discovery of previously undetected novel autoantigens. Further experiments will address its role in ERU pathology

Risk of hypoglycaemia with insulin degludec versus insulin glargine U300 in insulin-treated patients with type 2 diabetes : the randomised, head-to-head CONCLUDE trial

Aims/hypothesis A head-to-head randomised trial was conducted to evaluate hypoglycaemia safety with insulin degludec 200 U/ml (degludec U200) and insulin glargine 300 U/ml (glargine U300) in individuals with type 2 diabetes treated with basal insulin. Methods This randomised (1:1), open-label, treat-to-target, multinational trial included individuals with type 2 diabetes, aged ≥18 years with HbA1c ≤80 mmol/mol (9.5%) and BMI ≤45 kg/m2. Participants were previously treated with basal insulin with or without oral glucose-lowering drugs (excluding insulin secretagogues) and had to fulfil at least one predefined criterion for hypoglycaemia risk. Both degludec U200 and glargine U300 were similarly titrated to a fasting blood glucose target of 4.0–5.0 mmol/l. Endpoints were assessed during a 36 week maintenance period and a total treatment period up to 88 weeks. There were three hypoglycaemia endpoints: (1) overall symptomatic hypoglycaemia (either severe, an event requiring third-party assistance, or confirmed by blood glucose [<3.1 mmol/l] with symptoms); (2) nocturnal symptomatic hypoglycaemia (severe or confirmed by blood glucose with symptoms, between 00:01 and 05:59 h); and (3) severe hypoglycaemia. The primary endpoint was the number of overall symptomatic hypoglycaemic events in the maintenance period. Secondary hypoglycaemia endpoints included the number of nocturnal symptomatic events and number of severe hypoglycaemic events during the maintenance period. Results Of the 1609 randomised participants, 733 of 805 (91.1%) in the degludec U200 arm and 734 of 804 (91.3%) in the glargine U300 arm completed the trial (87.3% and 87.8% completed on treatment, respectively). Baseline characteristics were comparable between the two treatment arms. For the primary endpoint, the rate of overall symptomatic hypoglycaemia was not significantly lower with degludec U200 vs glargine U300 (rate ratio [RR] 0.88 [95% CI 0.73, 1.06]). As there was no significant difference between treatments for the primary endpoint, the confirmatory testing procedure for superiority was stopped. The pre-specified confirmatory secondary hypoglycaemia endpoints were analysed using pre-specified statistical models but were now considered exploratory. These endpoints showed a lower rate of nocturnal symptomatic hypoglycaemia (RR 0.63 [95% CI 0.48, 0.84]) and severe hypoglycaemia (RR 0.20 [95% CI 0.07, 0.57]) with degludec U200 vs glargine U300. Conclusions/interpretation There was no significant difference in the rate of overall symptomatic hypoglycaemia with degludec U200 vs glargine U300 in the maintenance period. The rates of nocturnal symptomatic and severe hypoglycaemia were nominally significantly lower with degludec U200 during the maintenance period compared with glargine U300

Genetic and other factors determining mannose-binding lectin levels in American Indians: the Strong Heart Study

<p>Abstract</p> <p>Background</p> <p>Mannose-binding lectin (MBL) forms an integral part of the innate immune system. Persistent, subclinical infections and chronic inflammatory states are hypothesized to contribute to the pathogenesis of atherosclerosis. MBL gene (<it>MBL2</it>) variants with between 12 to 25% allele frequency in Caucasian and other populations, result in markedly reduced expression of functional protein. Prospective epidemiologic studies, including a nested, case-control study from the present population, have demonstrated the ability of <it>MBL2 </it>genotypes to predict complications of atherosclerosis,. The genetic control of <it>MBL2 </it>expression is complex and genetic background effects in specific populations are largely unknown.</p> <p>Methods</p> <p>The Strong Heart Study is a longitudinal, cohort study of cardiovascular disease among American Indians. A subset of individuals genotyped for the above mentioned case-control study were selected for analysis of circulating MBL levels by double sandwich ELISA method. Mean MBL levels were compared between genotypic groups and multivariate regression was used to determine other independent factors influencing <it>MBL2 </it>expression.</p> <p>Results</p> <p>Our results confirm the effects of variant structural (B, C, and D) and promoter (H and Y) alleles that have been seen in other populations. In addition, MBL levels were found to be positively associated with male gender and hemoglobin A1c levels, but inversely related to triglyceride levels. Correlation was not found between MBL and other markers of inflammation.</p> <p>Conclusion</p> <p>New data is presented concerning the effects of known genetic variants on MBL levels in an American Indian population, as well as the relationship of <it>MBL2 </it>expression to clinical and environmental factors, including inflammatory markers.</p

High levels of serum mannose-binding lectin are associated with the severity of clinical signs of leptospirosis

The clinical heterogeneity observed in leptospirosis may be associated with host factors or bacteria virulence. Human serum mannose-binding lectin (MBL) recognizes many pathogens, and low levels of this lectin are associated with susceptibility to infection. MBL is also implicated in the modulation of the inflammatory process. We determined the levels of serum MBL during leptospirosis infection. A double-antibody sandwich ELISA was used to detect the immunoreactive serum MBL. The ELISA plates were coated with monoclonal antibody to MBL and bound MBL or recombinant human MBL were detected by rabbit anti-human MBL serum. HRPO-conjugated goat anti-rabbit antibody was used for detection of the reaction. Two groups of patients seen at referral hospitals in Recife, PE, Brazil, were divided according to the year of infection, 2001 (N = 61) or 2002 (N = 57) and compared in terms of disease severity and levels of serum MBL. A group of healthy volunteers (N = 97) matched by age, gender, and ethnic background was used as control. Patients infected in 2001 had more severe outcomes than those infected in 2002, including jaundice, hemorrhage, respiratory alteration, and renal complication (P = 0.0009; chi-square test). The frequency of patients producing serum MBL >1000 ng/mL was higher in the 2001 group than in the 2002 and control groups (P < 0.01), suggesting an association of MBL level with disease severity. The involvement of MBL and genetic variation of the MBL2 gene should be further evaluated to establish the role of this lectin in the pathogenesis of leptospirosis